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| author | Frederic Weisbecker <fweisbec@gmail.com> | 2009-12-31 03:52:25 +0100 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2010-01-13 09:32:54 +0100 |
| commit | c2c5d45d46c8c0fd34291dec958670ad4816796f (patch) | |
| tree | 3d65ac0b76107abb6cf30982f69ccb9120de5be7 | |
| parent | Linux 2.6.33-rc4 (diff) | |
| download | linux-c2c5d45d46c8c0fd34291dec958670ad4816796f.tar.xz linux-c2c5d45d46c8c0fd34291dec958670ad4816796f.zip | |
perf: Stop stack frame walking off kernel addresses boundaries
While processing kernel perf callchains, an bad entry can be
considered as a valid stack pointer but not as a kernel address.
In this case, we hang in an endless loop. This can happen in an
x86-32 kernel after processing the last entry in a kernel
stacktrace.
Just stop the stack frame walking after we encounter an invalid
kernel address.
This fixes a hard lockup in x86-32.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1262227945-27014-1-git-send-regression-fweisbec@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | arch/x86/kernel/dumpstack.c | 14 |
1 files changed, 8 insertions, 6 deletions
diff --git a/arch/x86/kernel/dumpstack.c b/arch/x86/kernel/dumpstack.c index c56bc2873030..6d817554780a 100644 --- a/arch/x86/kernel/dumpstack.c +++ b/arch/x86/kernel/dumpstack.c @@ -123,13 +123,15 @@ print_context_stack_bp(struct thread_info *tinfo, while (valid_stack_ptr(tinfo, ret_addr, sizeof(*ret_addr), end)) { unsigned long addr = *ret_addr; - if (__kernel_text_address(addr)) { - ops->address(data, addr, 1); - frame = frame->next_frame; - ret_addr = &frame->return_address; - print_ftrace_graph_addr(addr, data, ops, tinfo, graph); - } + if (!__kernel_text_address(addr)) + break; + + ops->address(data, addr, 1); + frame = frame->next_frame; + ret_addr = &frame->return_address; + print_ftrace_graph_addr(addr, data, ops, tinfo, graph); } + return (unsigned long)frame; } EXPORT_SYMBOL_GPL(print_context_stack_bp); |